1. Field of the Invention
The present invention relates to a specimen box for an electron microscope, especially to a specimen box with one or more through holes, for use with an electron microscope.
2. Description of Related Art
As known in the prior art, a vacuum environment inside an electron microscope is critical for high resolution and accuracy during the observation of specimens under an electron microscope. Considering the vacuum environment, the conventional electron microscope is usually used to observe the structures of solid substances or specimens, such as dehydrated bio-tissue or dehydrated virus. Therefore, the conventional electron microscope has a limitation on the selection of specimens and is invalid for the dynamic observation of specimens.
The application of the electron microscope is restricted by the limitation on the selection of specimens. In order to resolve the above-mentioned drawbacks, a specimen box for an electron microscope suitable for the observation of specimens (such as chemical particles, biochemical molecules, or bio-tissues) in a gas or liquid state was proposed. After the specimen is injected into this specimen box, a sealant or a polymer sealant is used for sealing the specimen box. However, the sealant may easily absorb liquid from the specimen, and the vacuum degree of the electron microscope may be degraded due to the easy evaporation of liquid from the specimen into the vacuum environment through the polymer sealant. Accordingly, the resolution and the observation efficiency of the electron microscope would be greatly affected by the above-mentioned factors.
Another specimen box for an electron microscope was also suggested to solve the above-mentioned issues. The specimen box further includes a gas chamber and a buffer chamber in addition to the specimen chamber. The gas chamber of this specimen box is filled with inert gas to slow down gas diffusion and liquid evaporation from specimens. However, the inert gas in the gas chamber may affect the resolution although the sealing issue is resolved with respect to the specimen box. In addition, the structure of this specimen box is complicated so the cost is increased.
In all of the current and above specimen boxes, none could be opened again (=reopen) after the gas or liquid specimen is injected and the specimen boxes are sealed. In the completely sealed condition, the closed space contains finite oxygen and medium, and thus the lifetime of the living tissues or cells is shortened. Due to their short lifetime, the long-term dynamic changes of the specimens cannot be observed and thus the observation of living tissues or cells is limited.
Not only that, in all of the current and above specimen boxes, the sealant and the polymer sealant used for sealing the boxes have the defect of absorbing the liquid from the specimens. Therefore, the vacuum degree of the electron microscope is easy to be degraded and the original storage condition of the specimens would be damaged due to the liquid evaporation from the specimens to the vacuum environment of the electron microscope.
According to the above, providing a specimen box with high sealing and reopening features could not only effectively improve the observation of gas or liquid specimens under an electron microscope, but also greatly increase the kinds of specimens applicable to electron microscope observation.